
<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>jQuery UI Sortable - Drop placeholder</title>

  <style>
  #sortable { list-style-type: none; margin: 0; padding: 0; width: 60%; }
  #sortable li { margin: 0 5px 5px 5px; padding: 5px; font-size: 1.2em; height: 1.5em; }
  html>body #sortable li { height: 1.5em; line-height: 1.2em; }
  .ui-state-highlight { border:1px solid red;height: 1.5em; line-height: 1.2em; }
  </style>
  <script src="../script/jquery-3.3.1.min.js"></script>
<script src="../script/jquery-ui.min.js"></script>
  <script>
  $( function() {
    $( "#sortable" ).sortable({
      placeholder: "ui-state-highlight"
    });
    $( "#sortable" ).disableSelection();
  } );
  </script>
</head>
<body>
 
<ul id="sortable">
  <li class="ui-state-default">Item 1</li>
  <li class="ui-state-default">Item 2</li>
  <li class="ui-state-default">Item 3</li>
  <li class="ui-state-default">Item 4</li>
  <li class="ui-state-default">Item 5</li>
  <li class="ui-state-default">Item 6</li>
  <li class="ui-state-default">Item 7</li>
</ul>
 
 
</body>
</html>